Electric controller construction



Q13. A. FEASMUSSEN ELECTRIC CONTROLLER CONSTRUCTION Feb 1, 1938.

2 Sheets-Shea?- 1 Filged March 4, 1955 IN VENTOR.

n a w 4 0 P v A X m W M 9% r m w 5 ATTORNEY.

Feb. I, 1938. c. A. RASMUSSEN 2,107,045

ELECTRIC CONTROLLER CONS TRUCTION Filed March 4, 1935 2 Sheets-Sheei 2.mmm

INVENTOR.

0712;925:227 fi. Rasmussen. V

F1910; g p

ATTORNEY.

Patented Feb. 1, 1938 UNITED STATES PATENT OFFICE 5 Claims.

This invention relates to electric controllers and more particularlyrelates to the construction of controllers of the so-called drum type,which comprise generally a rotatable element having an electric contactor a plurality of electric contacts rotatable in a generally cylindricalpath into and out of electrical engagement with a correspondingstationary contact or a plurality of contacts.

Among the objects of the invention are:

To provide generally an improved electric controller; I

Toprovide an improved electric controller of the drum type;

To provide a drum type controller of improved construction providingincreased durability; simplification of parts and convenience ofmanufacture; improved facility of assembling and disassembling; andimproved construction of supporting frame or enclosing housing of theWorking parts. p

Other objects will be apparent to those skilled in the art to which myinvention appertains.

My invention is fully disclosed in the following description taken in.connection with the accompanying drawings, in which:

Fig. 1 is a side elevational view of a controller embodying myinvention;

Fig. 2 is a cross-sectional view taken from the plane 2-2 of Fig. 1,with parts back of the section plane omitted for simplicity;

Fig. 3 is a cross-sectional view taken from the plane 3-3 of Fig. 1;

Figs. 4, 5 and 6 are respectively top, side and end views of one form ofelectric contact which I may employ;

Figs. 7 and 8 are respectively side and end views of another form ofelectric contact;

Figs. 9 and 10 are respectively side and end views of another form ofelectric contact;

Fig. 11 is a fragmentary view similar to a part of Figs. 1 and 2illustrating a modification;

Fig. 12 is a view illustrating still another modification.

Referring to the drawings, I have shown a main frame or housing for thecontroller comprising opposite end members I and 2 which mayconveniently be made from cast metal, a bottom 3 preferably made fromsheet metal, and a cover 4 preferably made from sheet metal.

The bottom 3 as shown in Fig. 2 comprises. a generally fiat floor withbosses 5 pressed therein to serve as feet and having perforations 6therein by which the bottom and therefore the housing generally may bebolted to a support.

The bottom has sides l--'l bent upwardly therefrom, bolted as at 88 tolugs: 99-, formed on the end members. and extending inwardly. The lowerportion of the end of each end member I and? is grooved as at i0 and theend edges of the bottom 3 as at H are projected into the groove in; andby the construction above described, the bottom 3 is rigidly joined tothe end members i and 2. p

The end members I and 2 are rounded in their upper portion and the sheetmetal cover 4 is bent to conform thereto and rests upon shouldersl2--l2' and may be secured on the end members i and 2 to cover theinterior of the housing in any suitable manner convenient for itsremoval to give access to the interior, for example by screws l3threaded in the sides 1-! and projected through downwardly open notches[4 in the lower edges of the cover 4 whereby the heads of the screws Itmay clamp the engaged portions of the cover upon the sides 'l 'l.

inwardly extending brackets l5-l5 are provided preferably formedintegrally with the end members I and 2 and a contact-supporting panelI6 of insulating material is supported on the 5 brackets I5l5 andsecured thereto for example by screws ll-l I. A plurality of contacts,preferably arranged in pairs, are mounted on the panel 16, andpreferably these contacts are all identical in structure. 30

The contacts comprise each a support 18 comprising a base portion i9secured to the panel 16 and a depending arm 20 terminating at its lowerend in an outwardly extending finger 2 I. A hook member 22 is riveted asat 23 to the arm 20. A contact finger 24 is disposed generally dependingfrom the panel is and has on its lower end an inwardly convex portion ofrelatively short radius, 25, adapted to engagemovable contacts to bedescribed, and is provided with a perforation 26 telescope-d over thehook member 22' with the main body portion 2? of the contact fingersuperposed on the arm 20 of the contact support l8.

A wire spring 28 of generally helical form is telescoped over the hookmember 22, abutting at one end on the body 21 of the contact finger, andat its other end formed with a loop 29 engaging the hook member 22. Thespring 28 thus reacts by its resilience to exert resilient thrust 50inwardly on the. contact finger 24 to normally engage it with thesupport finger 2|; and upon engagement of movable contacts to bedescribed with the contact portion 25, the contact'finger 24 will have ayielding hinging movement around the upper end of its body portion 21resting upon the arm 26 of the contact support 18.

A clip member 30 rests upon the base I9 of the contact support l8 andhas a finger 3| projecting outwardly therefrom to suitably position aflexible connector of metal ribbon 32, one end 01' which is riveted asat 33 to the contact finger 24 and the other end of which is superposedupon the clip element 38. Connector bolts 33-33 are projected throughthe panel 16 and successively through the base l9, the clip member 30and the ribbon 32, and these parts are clamped together by a nut 34 torigidly secure them to the panel 16. Terminal nuts 35 on the screws 33provide for connecting electrical conducting wires 36 to the bolts 33and therefore electrically to the contact finger 24, through theconnector ribbons 32.

As shown in Figs. 1 and 2 there may be three pairs of contact fingers 24and wires 36 may lead therefrom to the electrical apparatus to becontrolled. The wires 36 may be carried out of the housing throughrelatively large perforations 3l3l in the end member 2 of the housing,the wires 36 being indicated in Fig. 2 but omitted from Fig. 1 forsimplification of the drawings.

The contact fingers 24 above described and the mechanism described inconnection therewith form no essential part of the instant invention.The movable contacts and the means of mounting the same will now bedescribed.

A drum shaft 38 is provided preferably formed from laminated insulatingmaterial and preferably square or otherwise rectangular in crosssection.To rotatably support the shaft 38 at the left end as viewed in Fig. 1, apivot bearing is provided comprising a pin or the like 39 extendinginwardly from the end member 2 and rigidly secured thereto in anysuitable manner, for example as by driving it into a perforation 40 inthe end member 2. The shaft 38 has a recess 4| coaxially thereof intowhich the pin 39 projects, and a metal ferrule 42 is fitted on the endof the shaft 38 and has a perforation 43 telescoped over the pin 39.

The shaft 38 may thus rotate on the pin by its recess 41 but preferablythe bearing support of the shaft 38 is taken on the perforation 43 ofthe metal ferrule. End thrust of the shaft 38 toward the left is takenby the ferrule 42 abutting upon a boss 44 formed on the end member 2.

To support the right-hand end of the shaft 38 as viewed in Fig. 1, arelatively large diameter boss 45 is provided on the end member, havinga relatively large diameter bore 46 therein coaxial with the shaft 38; abushing 41, externally cylindrical to rotatably fit the bore 36 has arectangular or square hole 48 therein by which the bushing 41 may bedriven or otherwise fitted on the end of the shaft 38; and the bushing41, inwardly of the boss 45, has an enlarged flange or collar 49 rigidlyconnected thereto or formed integrally therewith. If desired, a setscrew 50 may be provided in the sleeve 4'! to rigidly secure the sleeveto the shaft 38 against longitudinal shifting. End thrust of the shaft38 toward the right may be taken by the flange 49 on the boss 45.

An operating handle 5| is provided having a hand grip portion 52,preferably extending radially with respect to the shaft 38, and having aflange 53, which may be substantially of. the same diameter as thesleeve 41, secured to the sleeve by a plurality such as four screws 54projected through suitable perforations in the flange 53 and threadedinto the sleeve 41.

By this construction it will be apparent that upon oscillating thehandle 5| by the hand grip portion 52, the shaft 38 will be rotated onthe bearings above described and the shaft will be prevented from movinglongitudinally in either direction.

To remove the shaft 38 from the housing or to assemble it therewithtogether with the movable contacts mounted thereon and to be describedhereafter, the handle 5| may first be removed by removing the screws 54,and then the end member I may be removed by removing the screws 8 andthe screws ll; whereupon the shaft 36 may be removed with the ferrule 42on one end and the sleeve 41 on the other; and the assembling of theshaft may be performed in the reverse order.

The construction of the movable contacts or drum contacts will now bedescribed. As shown in Figs. 1 and 2, the contact fingers 24 may bedisposed in pairs, the finger of each pair on opposite sides of theshaft 38, three such pairs being indicated in Fig. 1. Cooperating witheach pair of fingers 24 is a plurality of contacts 55 mounted on theshaft 38 and disposed to make engagement with the contacting portion 25of the fingers 24 when the shaft is rotated.

In the preferred construction of mounting the contacts 55, a pair ofsheet metal arms 56-56 are clamped upon opposite flats of therectangular shaft 38 by a through bolt or rivet 5T projected throughperforations in the arms 56 and in the shaft, the arms comprisingcorresponding fiat portions 58-58 engaging the shaft, end portions 5959extending in opposite directions from the flat portions 58 and parallelthereto, the portions 59 being joined to the portions 58 by inclinedconnecting portions Gil-60 whereby the adjacent portions 59 of the twoarms 1 -3-56 may be disposed relatively closely together.

The contacts 55 are preferably of T-form in cross-section, beingproduced by cutting short lengths from an extruded copper or the likebar of T-section. The contacts 55, therefore, each comprise a headportion GI and a stem portion 62. The arm portions 59 above describedare disposed so that the stem portion 62 of the contact may be disposedand clamped therebetween by screws 6363 in a manner to be more fullydescribed. Four supplemental arms 64 are provided from sheet metalstrips, preferably the same size strip as the arms 56, generally ofdivergent U-form, comprising flat intermediate portions 65 and oppositeleg portions 66 diverging from each other at an included angle ofapproximately 90. One of the divergent legs 66 of each supplemental arm64 is laid flat upon each of the outer arm portions 59 of the arms 56,thus disposing the other divergent legs 66 of. the supplemental arms inpairs parallel to each other and relatively closely adjacent; andbetween each of the pairs, the stem 62 of a contact 55 is placed.

The clamping screws 63 referred to are now projected throughperforations in the contact stem 62, arm portions 59 and one of thedivergent legs 66 and threaded into the other divergent leg to clamp theparts together and clamp the contact stem 62 to position and support it.Screws 6'! are projected through the remaining two contact stems 62 andcorrespondingly through one of the adjacent divergent arms 66 andthreaded in the other pair of arms 66 to clamp th ecorrespondingcontacts and support them on the supplemental arms.

In this manner all four contacts are supported with the outer surfacesof their heads 55 substantially on the surface of a cylinder to equallyand suitably engage the contact fingers 24 when the shaft rotated.Furthermore, the contacts are rigidly connected to the shaft and move inunison therewith without yielding or lost motion. 7 The construction ofthe contact support just described will be seen to admit of cheap,simple manufacture from sheet metal strips and at the same time toprovide arigid structure; and the structure will be seen to consist ofonly two different kinds of bent metal parts such as an arm 56 and anarm 64. It is a further distinct advantage of this construction thateither one of the contacts 55 may be removed without disturbing theother contact 55. Preferably the contacts 55 are symmetrically formedwith respect to the stem 62 so that when the contact has worn at oneedge of the head it may be removed by loosening and removing the screwholding it and may be turned. around to present the other edge of thehead 55 for wear. Or, in like manner, either contact may be completelyremoved and replaced when that becomes necessary without disturbing anyof the other contacts.

One form of contact 55 which may be employed is shown in Figs. 4, and 6and when this type is used, contact connection is made from one contactfinger 24 directly through to the opposite finger. In Figs. 7 and 8 isillustrated another type of contact, one of which is shown at 68 in Fig.1, and this form may be used when it is desired to bridge two of thefingers 24 on the same side of the drum.

In Figs. 9 and 10 is illustrated another form of contact comprising twostem portions 62 and a circumferentially extended head 550 forcontinuously engaging a stationary contact upon rotation of the drumthrough a predetermined angle.

In the modification of the contact support illustrated in Fig. 11,provision is made to dispose contact 55a opposite the edges of therectangular shaft 38 instead of opposite the flat portions thereof as inFig. 2, and this arrangement may be employed for engagement with some ofthe fingers 24 together with the arrangement of Fig. 2 when it isdesired to engage fingers 24 at each angular movement of the shaft 38 of45 instead of 90 as in Fig. 2; or the arrangement of Fig. 9 may be usedalternatively with that of Fig. 2 if desired. Substantially the onlydifference between the two forms is that the inner arms 56a of Fig. 9conform to the angular edges or corners, such as 69 of the shaft,instead of conforming to the flats thereof. In this form it may bedesirable to countersink the ends of the rivet or bolt 51a asillustrated.

In the modification of Fig. 12, a simplified form is shown whichdisposes the contacts 55b opposite the angular edges of the shaft 38 asin the form of Fig. 9. In this form the inner arms are dispensed with.Four similar or identical U-shaped arms 10 are provided having flatintermediate portions 'H and opposite diverging legs 12, diverging at anangle of 90 with each other. The intermediate portions H of two of thearms are disposed on opposite flats of the shaft 38 and rigidly securedthereto by a bolt or rivet 13. The other arms II have their intermediateportions 12 resting upon the other two fiat faces of the shaft 38 andmay likewise be secured rigidly to the shaft 38 by a bolt or rivet butneed not be so secured, being held position by the arms which aresecured by the bolt 13 in the following manner.

The stems of the contacts55b are disposed between the adjacent pairs ofdivergent legs 12 and secured therebetween by screws 14 projectedthrough one. of the legs 12 and through the stems of the contacts andthreaded into the other divergent leg. This means of securing contactsis In order 'to stop or fcenter the shaft in the several positions inwhich the contacts on the drum are in engagement with the contactfingers 24, the flange 49 which, as-above described is secured to theshaft, is provided with teeth 15. A roller 16 ona lever I1 pivoted tothe end frame member I at,'l8 is springepressed into engagement with theteeth by a spring 19 secured at one end to the lever 11 and at the otherend to the frame member I as at. Upon turning the shaft 38, the rollerHi wlllride up out of the space between adjacent teeth and permittheshaft to turn and willride down on the other side of the tooth overwhich it has ridden, and thus predetermine exact rotative positions forthe shaft 38. Any number of positions may be provided by a correspondingnumber of teeth. To stop rotative movement of the shaft 38 in extremepositions in. each direction, when this is desired, a stop 8| may beformed on the end frame member I engageable with shoulders 82 and 83 onthe flange 49.

My invention is not limited to the exact details of construction shownand described inasmuch as changes and modifications may be made thereinwithout departing from the spirit of my invention or sacrificing itsadvantages and within the scope of the appended claims.

I claim:

1. In a controller drum construction, a shaft, a plurality of contactcarrying arms extending laterally from the shaft comprising a likeplurality of identical sheet metal elements bent into divergent channelform with the web of the channel disposed adjacent to the shaft and eachflange of one element disposed adjacent to and generally parallel to aflange of the next adjacent element around the shaft, the generallyparallel pairs of flanges constituting the said arms, contact elementseach having a portion disposed between a corresponding pair of flangesrespectively and means to clamp them therebetween, and means to mountthe plurality of sheet metal elements on the shaft.

2. In a controller drum construction, a shaft, a plurality of contactcarrying arms extending laterally from the shaft comprising a likeplurality of identical sheet metal elements bent into divergent channelform with the web of the channel disposed adjacent to the shaft and eachflange of one element disposed adjacent to and generally parallel to aflange of the next adjacent element around the shaft, the generallyparallel pairs of flanges constituting the said arms, contact elementseach having a portion disposed between a corresponding pair of flangesrespectively, contact connecting means detachably rigidly connecting thecontact portions to the pairs of flanges respectively, and means tomount the sheet metal elements on the drum, comprising means to rigidlyconnect some of the said channel portions to the said shaft.

3. In a controller drum construction, a shaft, a plurality of contactcarrying arms extending laterally from the shaft comprising a likeplurality of identical sheet metal elements bent into divergent channelform with the web of the channel disposed adjacent to the shaft and eachflange of one element disposed adjacent to and generally parallel to aflange of the next adjacent element around the shaft, the generallyparallel pairs of flanges constituting the said arms, contact elementseach having a portion disposed between a corresponding pair of flangesrespectively, contact connecting means detachably rigidly connecting thecontact portions and the pairs of flanges together respectively, andmeans to mount the sheet metal elements on the drum comprising a pair ofsheet metal elements embracing the shaft therebetween and rigidlysecured thereto and having end portions extending laterally from theshaft and rigidly secured to corresponding ones of the first named sheetmetal elements.

4. In a controller drum construction, a shaft, a plurality of contactcarrying arms extending laterally from the shaft comprising a likeplurality of identical sheet metal elements bent into divergent channelform with the web of the channel disposed adjacent to the shaft and eachflange of one element disposed adjacent to and generally parallel to aflange of the next adjacent element around the shaft, the generallyparallel pairs of flanges constituting the said arms, a plurality ofcontact elements, and contact connecting means detachably rigidlyconnecting each contact element to a corresponding pair of flangesrespectively, and means to mount the sheet metal elements on the shaft.

5. In a controller drum construction, a shaft, a plurality of contactcarrying arms extending laterally from the shaft comprising a likeplurality of identical sheet metal elements bent into divergent channelform with the web of the channel disposed adjacent to the shaft and eachflange of one element disposed adjacent to and generally parallel to aflange of the next adjacent element around the shaft, the generallyparallel pairs of flanges constituting the said arms, a plurality ofcontact elements, contact connecting means detachably rigidly connectingeach contact element to a corresponding pair of flanges, respectively,and means to mount the sheet metal elements on the drum, comprising apair of sheet metal elements embracing the shaft therebetween andrigidly secured thereto and having end portions ex tending oppositelylaterally from the shaft and connected to corresponding ones of thefirst named sheet metal elements.

CHRISTIAN A. RASMUSSEN.

